The person who came up with this conjecture was Albert Einstein
Explanation:
Recession velocity of a galaxy is related to the distance at which the galaxy is located. This relationship is given by the hubble constant, as follows:

Hubble constant is aproximate
and 1 megaparsec (Mpc) is 3.26*10^6 light years. Rewriting for D:

For galaxy A:

For galaxy B:

The answer to your question is C.
The correct answer is:
<span>B) Ionic compounds form charged particles in solution, and electricity will only flow if charged particles are present.
In fact, in ionic compounds ions (which are charged atoms/molecules) are present in the solution, and these free charges can carry the electricity through the solution. Viceversa, in covalent compounds the valence electrons of the atoms are bound togethere between two atoms, so there are no free charges in the solution and electricity cannot flow.</span>